Vehicular tunnel ventilation design and application of CFD.

Ventilation requirements for vehicular tunnels in the Hong Kong Special Administrative Region are discussed. For vehicle emissions, carbon monoxide is considered to be important for vehicles running on petrol engines, and suspended particulates for diesel engines. Other environmental control parameters are temperature, air speed and air pressure. Codes, regulations and design guides for ventilation systems are reviewed. Different ventilation designs adopted in local vehicular tunnels are described. Better ventilation design for a typical vehicular tunnel is proposed with the application of Computational Fluid Dynamics. Numerical experiments on different cases including designing longitudinal ventilation system for smoke control were performed to justify the indoor environment